Microsoft's Strong Promotion of the New File System ReFS: What Does It Mean for Windows?

In the era of MS-DOS and Windows 9X, Microsoft used the FAT (File Allocation Table) file system. DOS and Windows 95 supported FAT16, which only allowed a maximum partition size of 2GB and a maximum file size of 2GB. Windows 98, while remaining compatible with FAT16, added support for FAT32, which allowed a maximum partition size of 2TB and a maximum file size of 4GB. After Windows 2000 and Windows XP, as the NT kernel became the mainstream, Windows has been using the NTFS (New Technology File System) as the default file system for PC hard disk storage, and this practice continues to this day.

For many home users, the replacement of FAT32 by NTFS was a significant step forward. After all, no one wants to be frustrated because a 4.5GB high-definition movie or compressed file package cannot be saved to a FAT32 hard drive, and having to search for file splitting software as a result (even today, some smart TVs and digital devices only support FAT32 external storage and cannot recognize NTFS and exFAT, which is quite astonishing). In recent years, Microsoft has been developing a new file system called ReFS, which stands for Resilient File System.

Objectively speaking, ReFS is not an entirely new technology, but it has not been widely adopted in Windows systems so far. However, recent findings show that during the installation process of Windows 11, users can choose to format the hard drive using the ReFS file system. This seems to indicate that ReFS has the potential to become the default file system for Windows in the future. But if it does become the default, let's take a closer look at ReFS and explore what it means for the future.

What is ReFS?

As its name implies, the Resilient File System is designed to enhance the resilience of the system and data. Microsoft states that this file system has multiple functions for error detection and correction, helping to prevent and repair data corruption, and reducing the impact on system stability.

ReFS includes a data integrity scanner that actively ensures the correctness and integrity of the data on the volume. It is optimized for Storage Spaces in Windows. So, if it detects data corruption on one volume, it can use another volume to repair the damaged data while allowing the volume to continue operating, ensuring that the data remains accessible. All of these processes are automated, so users don't have to bother trying to manually repair data corruption.

ReFS has actually been around for over a decade, but it has mainly been focused on Windows Server because data resilience and minimal downtime are particularly crucial for the normal operation of servers. It first appeared in Windows Server 2012 and has since been continuously updated with new features, such as support for data deduplication.

Even today, more than a decade later, ReFS is still not considered a complete replacement for NTFS. ReFS is more suitable for application scenarios such as servers and large-scale deployments, and it is not yet suitable for home use.

What are the Advantages of ReFS?

In addition to enhancing data resilience through error detection and correction, ReFS has added some features that are very useful in specific environments. One of the most noticeable advantages is the increase in file and volume size. According to Microsoft, ReFS can support files and volumes of up to 35PB (petabytes), which is 35,000TB. This is 100 times higher than the maximum limit of 256TB supported by NTFS. Of course, currently, very few home computers will be affected by exceeding the 256TB hard drive limit, so this may not have much practical significance for you.

ReFS also supports new features such as block cloning, sparse VDL, and mirrored accelerated parity. These features can significantly improve file operation performance in certain situations, such as when creating and merging VHDX files. When using Storage Spaces Direct, it can also improve performance across multiple volumes. Again, this feature is only available on Windows Server and Azure Stack HCI, and it also supports file-level snapshots.

In addition, ReFS supports most of the features of NTFS, such as BitLocker encryption, data deduplication, and Cluster Shared Volume support. However, it still lacks some key features required for home computers.

The Limitations of ReFS

Although ReFS has some obvious advantages over NTFS, it is clear that it cannot replace NTFS yet, and it is still a long way from being able to do so. Many features of NTFS are not supported in ReFS, which makes ReFS unable to be a solution for home PCs for now. These unsupported features include file system compression, file system encryption, support for bootable media, support for removable devices, object IDs, extended attributes, and disk quotas.

Due to the lack of some key features, ReFS is not really ready to fully replace NTFS. Considering that ReFS was originally designed for specific scenarios dealing with extremely large data sets, this is not really a defect. After all, ReFS was initially mainly targeted at large servers, not home computers.

Will ReFS Replace NTFS in Windows PCs?

Even though it cannot be applied to home computers currently, the support for larger hard drives and file sizes gives ReFS sufficient reason to potentially replace NTFS in the future. The question is how it can function better. When using multi-hard drive array storage, ReFS can actively repair data corruption, but most home PCs do not need this function, so its error correction ability is rather鸡肋 for most ordinary users. However, it is still much better than manually checking for data corruption using tools like chkdsk.

The same is true for performance improvements. ReFS is mainly designed around larger storage spaces and virtual hard drives. In the next few decades, the increase in hard drive capacity and file size will eventually affect home users. Back in 2000, you would have been satisfied with a 20GB hard drive, but who could have imagined that 4TB hard drives would be so common in 2025?

That is to say, Microsoft may not have a strong incentive to introduce ReFS into Windows 11 at present. The lack of features such as file system encryption and support for bootable media means that there is still some work to be done before ReFS can completely replace NTFS. And considering that ReFS doesn't offer many benefits to most ordinary users, Microsoft is not in a hurry to achieve this. ReFS will likely become the mainstream sooner or later, but it will still take some time before it becomes the default file system for most Windows users.

The Widespread Adoption of ReFS in the (Distant) Future

Although ReFS may be better than NTFS in some cases and is likely to replace NTFS at some point in the future, it is hard to imagine that it will bring about significant changes in the short term. ReFS was originally designed for large servers and deployments, and it will take some time before it can be truly suitable for home computers. Nevertheless, the advantages of ReFS still exist. Perhaps with the continuous development of technology, ReFS will become more meaningful than it is now.